Central air conditioning units gradually certified in accordance with the passive house standard

Frankfurt / Mülheim an der Ruhr, 12 March 2013 – Menerga GmbH obtains a "Passive House Suitable Component" certification for two of its product lines: the Resolair and Adconair central air conditioning units. This was announced by the company at ISH 2013 in Frankfurt. As a result, the ventilation and air conditioning equipment manufacturer based in Mülheim is one of the first providers, whose central air conditioning units have been tested in accordance with the criteria of the Passive House Institute in Darmstadt (PHI) in the flow rate range of between 2,000 and 15,000 m3/h for non-residential buildings by an independent institute. Both series are equipped with ultra-efficient regenerative or recuperative heat recovery systems that are already fulfilling PHI requirements in a number of passive houses. The first product to obtain the certification was the Resolair unit version 640701 with a nominal flow rate of 6,000 m3/h. A heat provision level of more than 86% across the entire power range was determined which is significantly higher than the required value of 75%. At the same time, the unit also fulfils the comfort criterion (SA 16.5° C at OA -10° C) of a 4,500 m³/h volume flow rate, also without additional heating coil.

"Nowadays, passive houses are not just popular in the private sector, but also in the sector of non-residential buildings. This has been demonstrated in the continual increase in demand for our ultra-efficient Resolair plants for exactly this area of application in recent years. Thanks to the passive house certification, we can now give our customers the security that our plants are ideally suited to the implementation of these challenging projects," says Executive Director Dr. Christian Hennerkes. "Following the successful certification of the first version of the unit, we will now gradually provide full verification for both product series. The PHI certification programme extends to an air volume flow rate of max. 15,000 m³/h, whereby our plants also meet the strict criteria far beyond this level."

The central element of the certification process is the determination of the performance data by an independent testing institute. The Essen-based DMT GmbH which is part of the TÜV Nord Group was entrusted with this task. Based upon the regenerative heat recovery system with two fixed heat storage masses, the Resolair unit achieved a maximum heat provision level of above 87% here. In doing so, the permissible limiting value in terms of the specific electrical power consumption of 0.45 Wh/m3 was constantly observed in the range between 3,000 and 4,500 m³/h as a result of the low internal pressure losses. In addition, the unit achieves this high level of efficiency with extremely compact dimensions of 4.660 x 1.050 x 2.050 mm. Furthermore, the PHI comfort criterion of a flow rate of up to 4,500 m3/h is also achieved without reheating, meaning that it is possible to forego additional heating coils as well as lines and pumps that noticeably reduces both external pressure losses as well as investment costs.

The company based in Mülheim has also already started the process of certification of the Adconair unit series with a recuperative HRC system. The first product to obtain the certification was the Adconair unit version 761001 with a nominal flow rate of 6,000 m3/h. Here, a countercurrent plate heat exchanger has been deployed in a freely configurable HVAC system with nominal flow rates of multiple 10,000 m³/h for the very first time. This results in an extremely high heat recovery performance at low internal pressure losses, meaning that the units are ideally suited for use in passive house buildings. Recuperative HRC systems are primarily deployed in projects where odour transfer should be completely ruled out, e.g. in apartment buildings in accordance with the passive house standard. The first measurements, also performed by DMT, verified a heat provision level of up to 94. According to manufacturer information, such values cannot be achieved by classical recuperative heat exchangers that work based upon the crossflow or cross-countercurrent principle or can only be achieved by special, extremely elaborate unit configurations, especially at high air volume flow rates.